Combined smoke observation device and photoelectric indicating means



Aug. 4, 1942. R H, WAGER 2,291,776

COMBINED SMOKE OBSERVATION DEVICE AND PHOTO-ELECTRiC INDICATING MEANS Filed Jan. 16, 1941 4 Sheets-Sheetl WITNESS R. H. WAGER 2,291,776

COMBINED SMOKE OBSERVATION DEVICE AND PHOTO-ELECTRIC INDICATING MEANS Aug. 4, 1942.

Filed Jan. 16, 1941 4 Sheets-Sheet 2 m wm m MPH! .luilu R. H. WAGER 4 Sheets-Sheet 5 Filed Jan. 16, 1941 A II:It:IllInIIInIII:IIIIlllllirnlniniinniil B H Wage? Aug. 4, 1942.

COMBINED SMOKE OBSERVATION DEVICE AND PHO'IO-ELECTRIC INDIGATING MEANS 'mrusss w R. H. WAGER 2,291,776

COMBINED SMOKE OBSERVATION DEVICE AND PHOTO-ELEETRIC INDICATING MEANS Aug. 4, 1942.

Filed Jan. 16, 1 941 4 Sheets-Sheet 4' Fig. 11.

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\ UNITE STATES FlCE COMBINED SMOKE OBSERVATION DEVICE AND PHOTOELEQTEIC INDICATING MEANS Robert Hudson Wager, Maplewood, N. J.

Application January 16, 1941, Serial No. 374,751

- 6 (Balms.

For many years, devices have been in use for visually inspecting the condition of smoke dismeans which in turn reflect it on to such a stais to provide a combined visual and electrical device in which the light sensitive signal control element, even though controlled'by the same beam of light which is received and reflected by the reflecting means, will not obstruct said beam and will cast no shadow on said reflecting means.

A further object is to provide a novel construction which will thoroughly encase and protect the light-sensitive element.

broken away and in section showing the invention operatively associated witha smoke passage.

Fig. 2 is an enlarged vertical sectional view through the structure shown at the upper right hand corner of Fig. l.

Figs. 3', 4 and T) are sectional views on the correspondingly numbered broken lines of Fig. 2. v

' Fig. 6 is a rear elevation of the reflecting mirror shown more particularly in Figs. 2 and 4.

Fig. 7 is an exaggerated horizontal sectional lvie'w on line 1-1 of Fig. 6.

'Fig. 8 is a side elevation of the indicating means.

Fig. 9 is a front elevation thereof. Figs. 10, 11, and 12 are sectional views on the correspondingly numbered broken lines of Fig. 9.

Insofar as the visual characteristics of the disclosed device are concerned, it is very similar Yet another object is to provide a novel construction in which both the reflecting means and the light-sensitive element are carried by a single housing door which may be easily substituted for the housing door l9 of my U. S. Patent 1,708,987 of April 16, 1929, covering a Smoke inspection device which has been successfully marketed for a number of years.

A still further aim'is to provide a novel construction which, while designed primarily for s oke condition observation and indication purposes, will not necessarily be limited to this field, but will be useable to advantage in other installations where it is desirable to combine, with a light-reflecting optical device, a light-sensitive work-performing element, in such manner that ings.

Figure l is a vertical sectional view partly Ill to the device disclosed in my Patent 1,708,987, above mentioned, and another of my patents N0. 2,1l8,'ll6'of May 24, 1938, also disclosing a smoke inspection device, For structural details, herein shown but not described, reference may be made to said patents. Furthermore, with reference 'to structural features which are described. herein, it is to be understood that while they are preferred, variations may be made within invention as claimed.

y A light-projecting unit I5 is shown for projecting a beam ofv light Iii across a smoke 'passage i1, and a mirror 18 is shown to receive said beam of light and reflect same to an observation station IS. The mirror I8 is disposed within a housing 20 having a light inlet connected with f the passage I! by an appropriate pipe 2|, said" housing 20 also having a light outlet connected ing means for normally holding it tightly closed. Withinthis housing 20 is a casing 26 having the mirror l8 atlone of its sides, said casing, while ordinarily being disposed in a plane at an angle of to the pipes 2| and 22, being universally adjustable to compensate for any irparts after installation. The universal adjusting :1"

is 'an electrical light-sensitive element 28 0115 regularities due to installation or to warping of means for the casing 26 is indicated at 21. This adjusting. means is in all substantial respects a duplicate of the mirror-adjusting means disclos in the two patents above mentioned. I

Within the casing 26, behind the mirror. l8,

the scope of the tomarily known as-a photo-tube, a tube identifled to the trade as RCA No. 919 being preferably employed. Also within the casing 26, I have disclosed an amplifying tube 29, RCA #6J7G being preferred. A coil 30 and suitable condensers 3| and 32 are also shown within the casing 26, these elements and the tubes 28 and 29 forming portions of a photo-electric indicating means, the indicating unit of which is disclosed at 33, said unit being appropriately connected with the elements within the casing 26 by means of a suitable cable 34. This cable passes through a grommet 35 in the door 23 and through a .stufling box 36 carried by the casing 26, said stufling box preventing any entrance of moisture and foreign matter around said cable.

The mirror I8 is provided with a non-reflecting portion 31 through which a sample of the light beam 16 may pass to the photo-tube 28, said portion-31 being very restricted so as to not materially interfere with the reflecting surface of the mirror. In the preferred construction, this restricted portion 31 of the mirror I8 is provided as described below.

The elements 28, 29 and 30 above described,

are preferably mounted on a single bracket ll secured by screws or the like 32 to a plate 43, which plate is in tum secured to the body of the casing 26 by screws or the like 44, said the face of the mirror [8, its non-reflecting lightpassing portion 31 may also be cleaned at the same operation. The casing 26 may be adjusted as required when initially installing and at any required time thereafter, and regardless of these adjustments to properly position'the mirror with respect to the light inlet and light outlet of the housing 20, the photo-tube 28 will remain in such position as to be adequately affected by the light beam sample received thereby.

The indicating unit 33 preferably includes a red bulls eye 5| to indicate excessive smoke, a green bulls eye 52 to indicate excessive air, and a white bulls eye 53 to indicate the proper combustion conditions. Electric lights 54 are provided for these bulls eyes, and switches for these lights are controlled by an ammeter-relay 55 which is in turn controlled by a meter 56 which the-accompanying drawings, it will be seen that novel and advantageous provision has been made for carrying out the above objects, andwhile preferred structural features have been illustrated, attention is again invited tothe possibility of making variations within the scope of plate 43 closing. the open side of said casing body and cooperating with the latter in forming the complete casing. A moisture-excluding gasket 45 is preferably interposed between the the invention as claimed.

I claim:

1. In a smoke inspection device having means for projecting a beam of light across a smoke passage, and a mirror for receiving said beam and reflecting same toward an observation station; a light-sensitive; smoke-indicator-controlelement mounted behind said mirror, said mirror is formed with a similar opening 48. The outer ends of the screws 44 secure a frame is to the casing body, which frame secures the mirror l8 in place. tween the frame 49 and the mirror to prevent breaking of .the latter when the screws I! are tightened.

When the invention is properly installed, the beam of light from the projector l5 will pass across the smoke passage I], will be received by the mirrorl8 and will be reflected on tothe observation station 19 at which the condition of the smoke may be seen. At the same time, a sample of the same beam passes through the non-reflecting portion 31 of the mirror and so affects the photo-tube 28 as to control the indicating unit 33, which unit indicates the condition of the smoke by suitable instruments and lights. 7

The door 23 and the parts carried thereby may readily be substituted for the mirror-carrying door l9 shown in Patent No. 1,708,987, or for the door 58 shown in Patent No. 2,118,716, and thus smoke inspection devices installed prior to the present improvements may be quicklyand easily equipped-with vsaid improvements. The casing 26 effectively protects all encased parts against moisture and any foreign matter. Whenever the door 23 is swung outwardly, the casing 26 and parts carried thereby move bodily with "said door as shown in dotted lines in Fig. 2. Thus, when outwardly swinging the door to clean A gasket or the like 58 is shown be-- having an entirely unobstructed non-reflecting portion through which a sample of the light beam may pass-without diminution to said light-sensitive element.

2. In a smoke inspection device having means for projecting a beam of light across a smoke passage, and a conventional mirror positioned to receive the beam and reflect same to an observation station, said mirror comprising a transparent plate and a light-reflecting coating on 'the rear side ofisaid plate; a light-sensitive smokeindicator-control-element mounted behind said mirror, said light-reflecting coating having a restricted opening providing said transparent plate with an entirely unobstructed portion through which a sample of the light beam may pass without diminution to said light-sensitive element,

3. In an optical device, a housing having a door, a light inlet and a light outlet, a mirror carried by and spaced inwardly from said door in position to receive a light beam entering through said inlet and to reflect said beam through said outlet, and a light-sensitive workperforming element carried by said door and located between the same and said mirror, said mirror having a restrimed non-reflecting entirely unobstructed portion through which a sample of said light beam may pass without diminution to said light-senstive element; said door, mirror and element being bodily movable outwardly from said housing to permit cleaning of the face' of tlon of said mirror.

4. In an optical device, a housing having a door, a light inlet and a light outlet, a casing and means adjustablv mounting the same on the inner side of said door, said casing having a mirror at one of its sides positioned to receive a light beam entering through said light inlet and to reflect said light beam through said light outlet, and a light-sensitive work-performing element mounted in said casing behind said mirror,

said mirror having a restricted entirely unob structed non-reflecting portion through which a sample of said light beam may pass without diminution to said light-sensitive element, said door and easing being outwardly movable bodily from said housing to permit cleaning of the face of said mirror and said restricted non-reflecting portion of said mirror.

5. In a device of the class described, a casing body having an open side, a rigid plate closing said open side'aud having an opening, a mirror backing lying-against the outer side of said plate and having an opening registering with said opening of said plate, a mirror comprising a transparent plate having a light-reflecting coating lying against said mirror backing, said coating having a restricted opening alined with the aforesaidopenings to admit rays of light into the casing, means securing said'mirror, backing and plate to said casing body, and a light-sensitive element mounted in said casing on said plate and disposed in the path of the admitted light rays.

6. In a device of the class described, a casing body having an open side, a rigid plate closing said open side and having an opening, a mirror at the outer side of said rigid plate and comprising a transparent plate having a light-reflecting coating on its rear side, said coating having a restricted opening alined with the aforesaid opening of said plate to admit rays of light into the casing, means securing said mirror and plate tofl'said casing body, and a light-sensitive element mounted in said casing on said plate and disposed inthe path of the admitted light ys. l

ROBERT HUDSON WAGER. 

